1. Identify four regions of the electromagnetic spectrum that astronomers use when observing objects in space. 2. List the three main types of optical telescopes and describe their differences.

3. Explain the advantages of putting a telescope into orbit around Earth.

The answer should be a

All of them are man made

the glands which are associated with each description is given below:

pancreas - is an endocrine and exocrine gland that secretes juices with enzymes for digestion. salivary glands- with protection and digestion in the mouth. liver- secretes bile for digestion.   lachrymal glands - secrete tears to moisten eyes and protect them from particles and infection.   sweat gland -regulates water, salt, and temperature. oil glands - to form a protective barrier on the skin.   goblet cells - secrete mucus for protection.